// app.js
App({
  onLaunch() {
    // 展示本地存储能力
    const logs = wx.getStorageSync('logs') || []
    logs.unshift(Date.now())
    wx.setStorageSync('logs', logs)

    // 登录
    wx.login({
      success: res => {
        // 发送 res.code 到后台换取 openId, sessionKey, unionId
      }
    })
  },
  globalData: {
    userInfo: null
  },


  // 设置监听器
watch: function (ctx, obj) {
  Object.keys(obj).forEach(key => {
    this.observer(ctx.data, key, ctx.data[key], function (value) {
      obj[key].call(ctx, value)
    })
  })
},
// 监听属性，并执行监听函数
observer: function (data, key, val, fn) {
  Object.defineProperty(data, key, {
    configurable: true,
    enumerable: true,
    get: function () {
      return val
    },
    set: function (newVal) {
      if (newVal === val) return
      fn && fn(newVal)
      val = newVal
    },
  })
}
})
